We will evaluate the effect of red blood cell (RBC) transfusion on fatal and non fatal events according to baseline risk of death in an international cohort of trauma patients (CRASH-2 trial). The following outcomes will be considered: death from all causes, death due to bleeding, death due to multiorgan failure, death due to vascular occlusive events and non vascular occlusive events. Non fatal outcomes include: myocardial infarction, stroke, deep vein thrombosis and pulmonary embolism.